F250 in Sig has 3130# of payload. 9 MPG Towing 8000lbs. 13-14 Empty. A 4.30 gear ratio will yield better mileage in stop and go and towing than a 3.73 which will have better unloaded highway mileage. Difference between the two is negligible...all depends on how you plan to use it. The GM 6.0 in the 3/4 tons has the lowest HP / Torque of the Big 3. Also.....a 3/4 ton will cost less to register in some states than the 1 ton will. 1 Ton's will often have an added weight fee attached to them. All things to consider. If you end up with the GM product...4.10 gears would be a good choice.